I've recently been working on this module:

https://github.com/OdooCommunityWidgets/website_multi_image/tree/8.0

which adds the ability to store a set of images on a product in a one2many relationship. I work with a large inventory all with a large number of photos that need to be displayed against a given product in an online catalog. This module creates the one2many to store the images, however I am unable to find any forum posts or documentation on importing/exporting into/out of a one2many relationship such as the one implemented in this module.

I would like to figure out how to import the default base64 at the moment, as I will be working on modifying these modules:

https://github.com/maxmumford/oe_import_product_images

https://github.com/maxmumford/odoo_product_images_csv

to make importing from image URL's or local file paths easier to allow for a more user-friendly way to mass import/update product image galleries in Odoo 8.0. The eventual goal of this will be to create a module to add extra functionality to the default import/export functionality of Odoo to allow for a Magmi (a Magento tool) like syntax for importing product images into a gallery against a product or product variant.

Any suggestions or advice on how to achieve an import into a one2many relationship would be very much appreciated.